A demonstration was developed to
introduce students to waste valorization
in order to form bioplastics. Waste valorization is the process of
reusing, recycling, or composting, from waste, useful products or
sources of energy. In this demonstration, waste valorization is introduced
by converting sour milk into a bioplastic via the addition of lemon
juice upon heating. Utilizing lemon juice to perform the acidification
offers a greener procedure than the traditional formaldehyde (used
commercially to make galalith) and enhances the transferability in
remote locations such as the Amazon Rainforest in comparison to vinegar.
Students can establish connections to relevant United Nations Sustainable
Development Goals (UN SDGs) by adopting a systems thinking approach.
However, through this, it is noteworthy that this process is also
used (particularly in the Indian subcontinent) to make paneer, a farmer
cheese. While this also enables students to make a link to additional
UN SDGs pertaining to “zero hunger”, there is an ethical
discussion to be had as to whether such a process that is utilized
to feed malnourished citizens should be used to make a decorative
bioplastic. As such, despite this demonstration being transferrable,
instructors may consider carefully whether to utilize this resource,
and, if so, to use this as an opportunity to teach the importance
of ethics in science.